Equine herpesvirus outbreak spreads through Europe forcing cancellation of FEI World Cup Finals.

An Equine Herpesvirus outbreak in the Spanish city of Valencia has locked down the equestrian sector and forced the cancellation of the FEI World Cup Finals.

The first case was diagnosed in early March as the neurological form EHV-1. Twelve horses have already died and more than 100 are affected.

The outbreak happened at a venue hosting events for the annual Sunshine tour, when hundreds of performance horses travel across southern Europe to compete in FEI events.

Read more about Equine Herpes virus here.

The first horse to show symptoms was a Belgian mare who was well-enough to compete for two weeks before showing symptoms. Then it took some days for the test results to trigger a lockdown.  During that time, many horses entered and exited the competition venue unaware and have spread the disease to other countries. There are 1500 horses stabled at the venue.

Of the twelve deaths (as at 13th March), five have died at an equine hospital in Valencia, two at the event venue, two in Barcelona and two in Germany.

There are now eight countries with confirmed cases: Spain, Germany, Belgium, France, Sweden, Italy, Switzerland and Qatar.

As this is a particularly aggressive strain of Equine Herpesvirus, and to aid implement the lockdown, the FEI has blocked all of the original in-contact horses from the FEI Database until testing protocols are fulfilled. National authorities are urging horse owners returning from competitions to implement strict biosecurity protocols to prevent spread of this fatal disease.

FEI events have been cancelled in ten European Nations, Austria, Belgium, Estonia, France, Germany, Italy, Netherlands, Poland, Portugal and Sweden. However, the FEI strongly recommends that all National Federations in mainland Europe cancel their national events in order to minimise horse movements.

The Longines FEI Jumping World CupTM Final were scheduled to be held in Gothenburg, Sweden, from March 31 to April 4, 2021.

For up-to-date facts and figures from the FEI click here.

EHV is endemic in many countries, including Australia and New Zealand, but the focus now is on minimising the transmission of this particularly problematic strain. The severity of the outbreak and resulting lockdown is likely to trigger much needed research and review of biosecurity and horse movements.

FEI Secretary General Sabrina Ibañez said; “Nobody wants to see an outbreak like this ever again. There will be a comprehensive and fully transparent investigation into every aspect of this outbreak, the way it has been handled,  and the findings will be published so that, together with the community, we can all learn from this.”

Equine Herpesvirus causes respiratory and neurological disorders and abortions. There are nine different strains but EHV type 1 and 4 are the most significant as they produce the most virulent, easily communicable and most costly outbreaks across equine industries, all over the world.

Equine Herpes Virus can be transmitted directly from horse to horse, but similar to Covid-19, it can be transmitted by droplets in the air, which can travel long distances when a horse coughs. Exposure to virus particles in the environment on fences, gear, water troughs, clothing, shoes, etc., can also produce infection.

Once horses have been affected with Equine Herpesvirus, they can continue to be carriers for life, and can begin to spread the virus and infect susceptible horses around them during times of stress.

The evidence, so far, suggests EHV infection begins in the respiratory tract and, once the virus multiplies enough in susceptible horses, it gets into their blood stream where it produces a ‘viremia’. This just means virus in the blood. If there is a large enough amount of virus in the blood, it gets into the central nervous system where it can damage the brain and spinal cord, leaving horses unable to stand.

Images and footage of extremely sick horses in Valencia are circulating on social media and other platforms, who are pointing out the similarities of the consequences of this disease with COVID-19.

The FEI has been working to improve the treatment of horses at the venue and provided additional veterinary support and medical supplies, with a total of 21 veterinarians now onsite.

Over the weekend, they ordered extra stabling so that healthy/recovered horses can be better separated from sick animals on venue to prevent further transmission. A total of 44 temporary stables, which are being transported from the South of France, are due to arrive soon and 22 boxes will also be supplied to the Valencia Equine Hospital in order to free up emergency treatment permanent stables.

Additionally, the French National Federation and the FEI have coordinated a supply of inflatable support mats to assist recumbent horses to stand. Rescue nets and emergency slings are being sourced from Switzerland. The French and German National Federations are also supplying extra veterinarians.

While there are vaccinations for EHV, there is very little evidence they can prevent the neurological form of the disease. Although a few studies have found modified live vaccines can reduce the severity, many questions are still unanswered.

The FEI has announced it will be using data gathered from this outbreak to evaluate the effectiveness of the EHV- 1 vaccine, seeing which horses in the total group of 752 that participated in Valencia have been vaccinated, which had symptoms or were asymptomatic, and which horses have died.

It is important to note that once horses are affected with Equine Herpes Virus, they can continue to be carriers for life. At times of stress, they may begin to spread the virus around in their environment and infect susceptible horses around them. For a more detailed and referenced report on some of research in this area click here.

While the neurological form of EHV (Equine Herpes Myeloencephalopahy, or EHM) is fairly rare in Australia and New Zealand, there is some evidence the incidence is increasing.